Muscle And Nerve Disease Flashcards
What are the common presentations of muscle disorders?
Weakness of skeletal muscle Short of breath (weakness of respiratory muscle) Poor swallowing (causing aspiration) Cardiomyopathy , arrhythmias Cramp Pain Stiffness Myoglobinuria
What are the common presentations not of babies with muscle disorders?
Poor suck and feeding
Failure to thrive
Floppy
What are their common signs of muscle disease?
Wasting/hypertrophy of muscles
Normal or reduces tone and reflexes
Myotone
Motor weakness
What are the common investigations for assessing muscle disorders?
History and examination Creating kinase (CK) EMG Muscle biopsy Genetic testing
is inflammatory muscle disease an example of a congenital or acquired muscle disease?
acquired
what is the pathology of muscular dystrophies?
cell degeneration - high creatinine kinase (CK)
lose all dystrophin
what is the difference between duchesses MD and Bekers MD?
duchesses muscular dystrophy shows loss of all dystrophin
in beckers there is only partial loss of dystrophin as well as abnormal dystrophin
what does myotonic dystrophy present commonly with?
cataract esp in people under 50yrs
what is the main feature of myotonic dystrophy?
muscles contract and are unable to relax
what channels are affected in familial hypokalaemia periodic paralysis?
Na, Ca, K
what channel is affected in hyperkalaemic periodic paralysis?
Na
what channel is affected in myotonia congenita?
Cl
what muscle diseases are the Na channels affected?
familial hypokalaemia periodic paralysis
hyperkalaemic periodic paralysis
paramyotonic congenita
in what type of muscle disease would you experience symptoms after short bursts of exercise?
disorders of carbohydrate metabolism - glycogenosis
in what type of muscle disease would you experience symptoms after a long endurance exercise?
disorders of lipid (fatty acid) metabolism
in what metabolic muscle disease would you find systemic and constant symptoms?
mitochondrial myopathies / cytopathies
name 2 inflammatory muscle diseases.
polymyositis
dernatomyositis
what investigations would you carry out for inflammation muscle disease?
Creatinine kinase (high)
EMG
biopsy
what would the biopsy show if it was positive for inflammatory muscle disease?
polymyositis - T cells and CD8 cells
dermatomyositis - B cells and CD4 cells
what is the treatment for inflammatory muscle diseases?
immunosuppression
what type of muscle diseases are paramyotonic congenital and myotonia congenital and whats the difference between the two?
channelopathies
paramyotonia congenita is due to Na channels
myotonia congenital is due to Cl channels
what is the pathophysiology of myasthenia gravis?
autoimmune disorders in which the body produces an antibody against the ACh receptors so no neurotransmitter is released
results in not being able to contract muscle
what is the clinical presentation of myasthenia gravis?
fatiguable weakness which progresses as the day goes on; in the limbs eyelids = ptosis talking swallowing shortness of breath diplopia muscles of mastication
what investigations are used to diagnose myasthenia gravis?
ACh receptor antibody
anti-MuSK antibody
assess neurophysiology by repetitive stimulation
CT chest - check for thymoma
what is the treatment for myasthenia gravis?
symptomatic - acetylcholinesterase inhibitor
immunosuppression
immunoglobulin / plasma exchange
thymectomy
what drugs are given for immunosuppression to treat myasthenia gravis?
prednisolone & steroid saving agent
what are some of the causes of generalised peripheral neuropathy?
hereditary vit B12 deficiency diabetes alcohol renal drugs infection: Lyme, leprosy paaneoplastic inflammatory demyelinating - Guillian Barre syndrome (acute) or chronic inflammatory
what are the symptoms and signs of disease/damage of the nerve root?
myotomal wasting and weakness
reflex change
dermatomal sensory change
what are the symptoms and signs if there is damage to an individual peripheral nerve?
wasting and weakness o innervated muscle
specific sensory change
what are the symptoms and signs of generalised peripheral neuropathy such as Guillian Barre syndrome?
ascending paralysis with sensory involvement (motor & sensory)
(this is because longest nerves are affected first)
what investigations are carried out to diagnose disorders of peripheral nerves?
blood tests i.e. TFT, LFT, renal test B12 test genetic analysis nerve conduction tests lumbar puncture nerve biopsy (usually for determining extent of treatment)
what is amyotrophic lateral sclerosis and what type of neurological disease is it?
amyotrophic lateral sclerosis means no muscle nutrition.
it is a progressive neurodegenerative disease that affects nerve cells in the brain and spinal cord
what part of the spinal cord is affected in amyotrophic lateral sclerosis and what effects does this have?
affects the anterior horn
therefor affects the motor neurones
what is the presentation of someone with amyotrophic lateral sclerosis?
usually affects the limbs then blubber i.e. swallowing then respiratory
there is a combination of UMN and LMN signs;
LMN = fasciculations, wasting and weakness
UMN = increased tone, brisk reflexes
no sensory involvement
how is motor neurone disease diagnosed?
combination of UMN and LMN signs
EMG
what is the treatment for motor neurone disease?
supportive i.e. PEG feeding, non-invasive ventilation, OT, SALT, physiology, care
Riluzole
palliative care
what is the prognosis for motor neurone disease?
3-5 yrs survival after symptom onset
2-3yrs after diagnosis
50% die within 14 months of diagnosis
what is the treatment for gillian barre syndrome?
IV immunoglobulins
